July 22, 2014

Focusrite ISA Two Microphone Preamplifier Overview

Debuting in March of 2012 at the Musikmesse show in Germany, Focusrite showed off its new microphone preamp based on the popular ISA One. The ISA One, and subsequently the ISA Two, are based around the ISA 110 which was a microphone preamp and equalizer that Rupert Neve developed for George Martin back in 1985. This makes the ISA Two not just another preamplifier but a preamp that was developed and endorsed by guys who really know their audio. All of the solid state circuitry on the Focusrite ISA Two is faithful to the original design, but the ISA Two gives you an extra, high quality input for your front end. Let’s take a closer look at what’s involved here with the Focusrite ISA Two and why you should consider getting one for your studio.


Focusrite ISA Two

The ISA Two is a dual mono microphone preamplifier. It’s a two channel version of the original ISA One for users looking to double up on their Focusrite preamps. The unit has variable input impedance which means you have four different values of input impedance to control on the front panel of the ISA Two. You can switch between low, medium, and high, and there is even a setting for the original ISA 110 input impedance. This is perfect if you have different types of microphones like ribbon, condenser, or dynamic.

There is an input selector on the front so you can select between microphone, line input, or instrument input. The ISA Two can get up to 80 db of gain which is pretty loud and should serve you well for nearly every recording situation. Most microphone preamps on the market at this price can only achieve around 70 db so if you need gain, the ISA Two delivers. On the front you have control over a high pass filter with a frequency range from 16Hz to 420 Hz and this is adjustable from the front panel. The back of the unit features a Peak Meter Calibration knob for controlling the metering level seen on the front panel. This is great if you are trying to get the inputs of the ISA Two to match the meter levels of your interface like on the Focusrite 18i20.

The usual suspects are available like switchable phantom power and a nice bright VU meter, but you also have a well built preamp here with all the knobs and switches feeling very rugged and professional. While there is no switch to make the two mono channels into a single stereo channel, it is very easy to make the proper gain adjustments to get an even level form each individual input.

The Ins and the Outs

Focusrite ISA Two

On the back of the ISA Two are two XLR microphone inputs as well as two line inputs for the two channels available. You have balanced insert points including a balanced send and return I/O. The send and return I/O are switchable from the front panel. The inclusion of a send and return I/O on the back means you can route your outboard EQs or compressors to the ISA Two. The inputs on the front of the ISA Two include two instrument inputs with 1/4” jacks.

There is no digital output which should be noted up front to anyone thinking this is simply a high quality two channel interface. Instead of another audio interface, this is a tremendous compliment to your existing audio interface, or A-D converters, where you have two dedicated inputs for high quality recordings.

Why You Need One?

The ISA Two is great for folks who need one or two high quality microphone preamps in their system. It’s also for those who want to do high quality stereo recording. The ISA Two is actually great for people with a project or home studio who don’t need a massive amount of inputs, but rather one or two of a very high quality. If you are just recording vocals, or acoustic guitars, or even piano, having two inputs is all you are really going to need and the ISA Two caters specifically to these kinds of users. The price is what makes this a reality for the project/home studio user. You can now have studio quality microphone preamps in a box that retails for under $1000.

During the Summer of 2014, Focustrite are making the ISA Two even more appealing by lowering the price on this outstanding microphone preamp. You can get yours now by going to Feel free to ask us questions or give your feedback on the Focusrite ISA Two in the comments section below.